Dear Linux folks,
Can you share your experiences, which processors you choose for
your RAID6 systems? I am particularly interested in Intel
alternatives? Are AMD EPYC processors good alternatives for file
servers? What about ARM and POWER?
We currently use the HBA Adaptec Smart Storage PQI 12G SAS/PCIe 3
(rev 01), Dell systems and rotating disks.
For example, Dell PowerEdge R730 with 40x E5-2687W v3 @ 3.10GHz,
192 GB of memory, Linux 4.14.87 and XFS file system. (The processor
looks too powerful for the system. At least the processor usage
is at most at one or two thread.)
```
[ 0.394710] raid6: sse2x1 gen() 11441 MB/s
[ 0.416710] raid6: sse2x1 xor() 8099 MB/s
[ 0.438713] raid6: sse2x2 gen() 13359 MB/s
[ 0.460710] raid6: sse2x2 xor() 8910 MB/s
[ 0.482712] raid6: sse2x4 gen() 16128 MB/s
[ 0.504710] raid6: sse2x4 xor() 10009 MB/s
[ 0.526710] raid6: avx2x1 gen() 22242 MB/s
[ 0.548709] raid6: avx2x1 xor() 15406 MB/s
[ 0.570710] raid6: avx2x2 gen() 25699 MB/s
[ 0.592710] raid6: avx2x2 xor() 16521 MB/s
[ 0.614709] raid6: avx2x4 gen() 29847 MB/s
[ 0.636710] raid6: avx2x4 xor() 18617 MB/s
[ 0.642001] raid6: using algorithm avx2x4 gen() 29847 MB/s
[ 0.648000] raid6: .... xor() 18617 MB/s, rmw enabled
[ 0.654001] raid6: using avx2x2 recovery algorithm
```
```
$ more /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid6] [raid5] [raid4] [multipath]
md1 : active raid6 sds[0] sdah[15] sdag[14] sdaf[13] sdae[12] sdad[11] sdac[10] sdab[9] sdaa[8] sdz[7] sdy[6] sdx[5] sdw[4] sdv[3] sdu[2] sdt[1]
109394518016 blocks super 1.2 level 6, 512k chunk, algorithm 2 [16/16] [UUUUUUUUUUUUUUUU]
bitmap: 0/59 pages [0KB], 65536KB chunk
md0 : active raid6 sdai[16] sdc[0] sdr[15] sdp[13] sdo[12] sdn[11] sdm[10] sdl[9] sdk[8] sdj[7] sdi[6] sdh[5] sdg[4] sdf[3] sde[2] sdd[1]
109394518016 blocks super 1.2 level 6, 512k chunk, algorithm 2 [16/16] [UUUUUUUUUUUUUUUU]
bitmap: 0/59 pages [0KB], 65536KB chunk
unused devices: <none>
```
Kind regards,
Paul
<<attachment: smime.p7s>>
